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1.
Cancer Sci ; 115(4): 1129-1140, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38351514

RESUMO

Oncolytic viruses (OVs) possess the unique ability to selectively replicate within tumor cells, leading to their destruction, while also reversing the immunosuppression within the tumor microenvironment and triggering an antitumor immune response. As a result, OVs have emerged as one of the most promising approaches in cancer therapy. However, the effective delivery of intravenously administered OVs faces significant challenges imposed by various immune cells within the peripheral blood, hindering their access to tumor sites. Notably, neutrophils, the predominant white blood cell population comprising approximately 50%-70% of circulating white cells in humans, show phagocytic properties. Our investigation revealed that the majority of oncolytic vaccinia viruses (VV) are engulfed and degraded by neutrophils in the bloodstream. The depletion of neutrophils using the anti-LY6G Ab (1-A8) resulted in an increased accumulation of circulating oncolytic VV in the peripheral blood and enhanced deposition at the tumor site, consequently amplifying the antitumor effect. Neutrophils heavily rely on PI3K signaling to sustain their phagocytic process. Additionally, our study determined that the inhibition of the PI3Kinase delta isoform by idelalisib (CAL-101) suppressed the uptake of oncolytic VV by neutrophils. This inhibition led to a greater presence of oncolytic VV in both the peripheral blood and at the tumor site, resulting in improved efficacy against the tumor. In conclusion, our study showed that inhibiting neutrophil functions can significantly enhance the antitumor efficacy of intravenous oncolytic VV.


Assuntos
Neoplasias , Terapia Viral Oncolítica , Vírus Oncolíticos , Humanos , Vírus Oncolíticos/fisiologia , Vaccinia virus/fisiologia , Neutrófilos/patologia , Terapia Viral Oncolítica/métodos , Fosfatidilinositol 3-Quinases , Neoplasias/patologia , Microambiente Tumoral
2.
FASEB J ; 37(1): e22690, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36468880

RESUMO

Fatty amide hydrolase (FAAH) is a key degradation enzyme of the endocannabinoid system, mainly responsible for the hydrolysis of arachidonic acid ethanolamine (AEA). Previous investigations have shown that FAAH is involved in a series of biological processes, such as inflammation, immune regulation, and transmembrane signal transduction of neurons. Endogenous cannabinoids and cannabinoid receptors have been reported to participate in the regulation of bone homeostasis by regulating the differentiation of osteoblasts and osteoclasts. We hypothesized that FAAH may play an important role in osteoclastogenesis based on the above evidence. The present study found that the FAAH expression was increased at both mRNA and protein levels during RANKL-induced osteoclastogenesis. Pharmacological and genetic inhibition of FAAH in bone marrow-derived macrophages (BMMs) inhibited osteoclastogenesis, F-actin ring formation, bone resorption, and osteoclast-specific gene expression in vitro. Moreover, intragastric administration of the FAAH inhibitor PF-04457845(PF) ameliorated ovariectomy (OVX)-induced bone loss in mice. Further investigation revealed that nuclear factor κB (NF-κB) and mitogen-activated protein kinase (MAPK) pathways were inhibited by PF treatment and FAAH knockdown. RNAseq indicated that the IL17 pathway was blocked by PF, and administration of recombinant murine IL17 protein could partially restore osteoclastogenesis and activate NF-κB and MAPK pathways. To sum up, our findings demonstrate that targeting FAAH could be a promising candidate strategy for treating osteoclast-related diseases, especially osteoporosis.


Assuntos
Amidoidrolases , Reabsorção Óssea , Interleucina-17 , Osteogênese , Animais , Feminino , Camundongos , Reabsorção Óssea/etiologia , Reabsorção Óssea/prevenção & controle , Diferenciação Celular , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Osteoclastos/metabolismo , Ovariectomia/efeitos adversos , Ligante RANK/metabolismo , Amidoidrolases/antagonistas & inibidores , Interleucina-17/metabolismo
3.
J Chem Phys ; 160(23)2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38884409

RESUMO

The oxygen reduction reaction (ORR), a pivotal process in hydrogen fuel cells crucial for enhancing fuel cell performance through suitable catalysts, remains a challenging aspect of development. This study explores the catalytic potential of germanene on Al (111), taking advantage of the successful preparation of stable reconstructed germanene layers on Al (111) and the excellent catalytic performance exhibited by germanium-based nanomaterials. Through first-principles calculations, we demonstrate that the O2 molecule can be effectively activated on both freestanding and supported germanene nanosheets, featuring kinetic barriers of 0.40 and 0.04 eV, respectively. The presence of the Al substrate not only significantly enhances the stability of the reconstructed germanene but also preserves its exceptional ORR catalytic performance. These theoretical findings offer crucial insights into the substrate-mediated modulation of germanene stability and catalytic efficiency, paving the way for the design of stable and efficient ORR catalysts for future applications.

4.
Phys Chem Chem Phys ; 25(20): 14359-14367, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37183725

RESUMO

3-Nitro-1,2,4-trihydroxy-5-one (NTO), a highly potential high-performance explosive with good thermal stability and low sensitivity, has attracted much attention for its physicochemical properties in recent years. In this work, the pressure effect of the vibrational and electronic properties is investigated to understand the intermolecular interaction of NTO under hydrostatic compression. From the pressure-dependent Raman and infrared spectra, we found that the red-shifts of high-wavenumber N-H stretching modes and the discontinuous shifts of all Raman modes occur at 3 and 6 GPa, indicating an evident change of molecular configuration and intermolecular interaction upon compression. Based on structural analysis, the changes of intra- and intermolecular hydrogen bonds (HBs) are closely relevant to the anomalous rotation of the nitro group and the lengthening of N-H bonds, which can be treated as an important step of a potential structural transformation of NTO. Moreover, intermolecular hydrogen-bonding interaction leads to the shrinkage of the band gap at 6 GPa, caused by the fast charge transfer of 0.07 e from the nitrogen heterocycle to the nitro group. These results manifest a non-covalent interaction mechanism for modulating the molecular configuration of EMs under pressure loading and provide vital insights into understanding the pressure effects for energetic molecular crystals.

5.
Surg Endosc ; 37(5): 3710-3719, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36650352

RESUMO

BACKGROUND: The self-help inflatable balloon (SHIB) and autologous skin-grafting surgery (ASGS) were used to prevent stricture after esophageal complete circular endoscopic submucosal dissection (cESD) with promising clinical results. We aim to evaluate which method is more suitable for patients who underwent esophageal cESD. METHODS: From October 2017 to July 2021, patients whose mucosal defect length were between 30 and 100 mm after esophageal cESD were retrospectively reviewed from two prospective studies. They were enrolled once SHIB or ASGS was used as preventive methods to prevent stricture. Propensity score matching (PSM) was used to balance the baseline characteristics between the two groups. Comparisons were made between the two groups, including operation time, the longitudinal length of ulceration, fasting time, hospitalization days, and the incidence of stricture. RESULTS: A total of 41 patients who met the inclusion criteria were enrolled in the study. The numbers of patients in SHIB group and ASGS group were 25 and 16, respectively. Fifteen patients in each group were selected after performing PSM. The basic baseline characteristics were comparable between the two groups. The stricture rates were 20% (3/15) in SHIB group and 40% (6/15) in ASGS group, while the difference was not statistically significant (p = 0.427). The SHIB group showed significantly shorter operation time, shorter hospitalization days, lower cost, and longer removing balloon/stent time compared with ASGS group (p < 0.001). Comparison of relevant stricture factors between the stricture group and non-stricture group revealed that longer longitudinal length of ulceration (> 60 mm) accounted for a higher proportion in stricture groups (p = 0.035). CONCLUSION: Both the SHIB and ASGS had high efficacy and safety in preventing strictures in patients with mucosal defects no longer than 100 mm in length after esophageal cESD. The longitudinal length of ulceration > 60 mm was the independent factor for predicting stricture.


Assuntos
Ressecção Endoscópica de Mucosa , Estenose Esofágica , Humanos , Constrição Patológica , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Neoplasias Esofágicas/cirurgia , Estenose Esofágica/etiologia , Estenose Esofágica/prevenção & controle , Estenose Esofágica/cirurgia , Pontuação de Propensão , Estudos Prospectivos , Estudos Retrospectivos
6.
J Chem Phys ; 159(4)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37489651

RESUMO

A comprehensive genetic algorithm is used to perform a global search for Cl-(H2O)1-9 and NaCl(H2O)1-9. The structural optimization, energy calculations, vibrational characteristics, and charge distribution were performed at an ab initio high-level theory. Combined with the calculation results of Na+(H2O)1-6 by Wang et al. [Front. Chem. 7, 624 (2019)] in our group, we systematically investigate these three systems at the same theoretical level. A comparison of bond lengths reveals that in Cl-(H2O)n, the inclusion of Na+ to form NaCl(H2O)n reduces the average distance between Cl- and H2O, indicating that Na+ has a stabilizing effect on ionic hydrogen bonds. Conversely, in Na+(H2O)n, the introduction of Cl- weakens the interactions between Na+ and H2O. In the NaCl(H2O)1-9 structures searched by the genetic algorithm, the ground-state configurations correspond to contact ion pairs, and the solvent-separated ion pair structures appear when n = 7. Furthermore, the anharmonic corrected infrared spectra of Cl-(H2O)1-5 and NaCl(H2O)1-4 exhibit good agreement with the experimental results. According to charge analysis of NaCl(H2O)n, it is observed that charge transfer primarily occurs from Cl- to H2O, resulting in the presence of negative charges on the water molecules. These findings are helpful to understand the effects of Na+ and Cl- on hydrated clusters at the molecular level.

7.
Eur Spine J ; 32(2): 590-600, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36350373

RESUMO

PURPOSE: We aimed to estimate the incidence, prevalence and years lived with disability (YLDs) of spinal cord injury (SCI) in China in 2019 and temporal trends from 1990 to 2019. METHODS: The Global Burden of Disease Study 2019 was used to obtain data. Outcome measures included age-standardized incidence rate (ASIR), prevalence rate (ASPR) and YLDs rate (ASYR). A Bayesian meta-regression tool, DisMod-MR 2.1, was used to produce the estimates of each value after adjustments. RESULTS: In 2019, there were 234.19 [95% uncertainty interval (UI) 171.84-312.87] thousand incident cases of SCI in China, with an ASIR of 13.87 (95% UI 10.15-18.66) per 100,000. ASIR and ASYR increased by 40.81% (95% UI 32.92-49.14%) and 11.44% (95% UI 5.16-17.29%) compared with 1990, individually. Males had higher ASIR and ASYR in each year from 1990 to 2019, but the incidence and YLDs rates of females exceeded males after 70 years old. Incidence and YLDs rates both ascended with age. SCI at neck level had slightly higher incidence rate but much higher YLDs rate than that below neck level. The average incidence age increased from 38.97 in 1990 to 54.59 in 2019. Falls were the leading cause of SCI. CONCLUSION: The incidence and burden of SCI in China increased significantly during the past three decades. The age structure of SCI patients showed a shift from the young to the elderly as population aging. Urgent efforts are needed to relieve the health pressure from SCI.


Assuntos
Carga Global da Doença , Traumatismos da Medula Espinal , Masculino , Feminino , Humanos , Idoso , Incidência , Prevalência , Teorema de Bayes , Saúde Global , Traumatismos da Medula Espinal/epidemiologia , China/epidemiologia , Anos de Vida Ajustados por Qualidade de Vida
8.
BMC Med Inform Decis Mak ; 23(1): 115, 2023 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-37415186

RESUMO

Deep learning models have been widely used in electroencephalogram (EEG) analysis and obtained excellent performance. But the adversarial attack and defense for them should be thoroughly studied before putting them into safety-sensitive use. This work exposes an important safety issue in deep-learning-based brain disease diagnostic systems by examining the vulnerability of deep learning models for diagnosing epilepsy with brain electrical activity mappings (BEAMs) to white-box attacks. It proposes two methods, Gradient Perturbations of BEAMs (GPBEAM), and Gradient Perturbations of BEAMs with Differential Evolution (GPBEAM-DE), which generate EEG adversarial samples, for the first time by perturbing BEAMs densely and sparsely respectively, and find that these BEAMs-based adversarial samples can easily mislead deep learning models. The experiments use the EEG data from CHB-MIT dataset and two types of victim models each of which has four different deep neural network (DNN) architectures. It is shown that: (1) these BEAM-based adversarial samples produced by the proposed methods in this paper are aggressive to BEAM-related victim models which use BEAMs as the input to internal DNN architectures, but unaggressive to EEG-related victim models which have raw EEG as the input to internal DNN architectures, with the top success rate of attacking BEAM-related models up to 0.8 while the top success rate of attacking EEG-related models only 0.01; (2) GPBEAM-DE outperforms GPBEAM when they are attacking the same victim model under a same distortion constraint, with the top attack success rate 0.8 for the former and 0.59 for the latter; (3) a simple modification to the GPBEAM/GPBEAM-DE will make it have aggressiveness to both BEAMs-related and EEG-related models (with top attack success rate 0.8 and 0.64), and this capacity enhancement is done without any cost of distortion increment. The goal of this study is not to attack any of EEG medical diagnostic systems, but to raise concerns about the safety of deep learning models and hope to lead to a safer design.


Assuntos
Aprendizado Profundo , Epilepsia , Humanos , Mapeamento Encefálico , Epilepsia/diagnóstico , Encéfalo , Eletroencefalografia
9.
Appl Environ Microbiol ; 88(8): e0002822, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35384707

RESUMO

Biomaterials offer unique properties that make them irreplaceable for next-generation applications. Fibrous proteins, such as various caterpillar silks and especially spider silk, have strength and toughness not found in human-made materials. In early studies, proteins containing long tandem repeats, such as major ampullate spidroin 1 (MaSp1) and flagelliform silk protein (FSLP), were produced using a large DNA template composed of many tandem repeats. The hierarchical DNA assembly of the DNA template is very time-consuming and labor-intensive, which makes the fibrous proteins difficult to study and engineer. In this study, we designed a circularized mRNA (cmRNA) employing the RNA cyclase ribozyme mechanism. cmRNAs encoding spider silk protein MaSp1 and FSLP were designed based on only one unit of the template sequence but provide ribosomes with a circular and infinite translation template for production of long peptides containing tandem repeats. Using this technique, cmRNAs of MaSp1 and FSLP were successfully generated with circularization efficiencies of 8.5% and 36.7%, respectively, which supported the production of recombinant MaSp1 and FSLP larger than 110 and 88 kDa, containing tens of repeat units. Western blot analysis and mass spectrometry confirmed the authenticity of MaSp1 and FSLP, which were produced at titers of 22.1 and 81.5 mg · liter-1, respectively. IMPORTANCE Spider silk is a biomaterial with superior properties. However, its heterologous expression template is hard to construct. The cmRNA technique simplifies the construction and expression strategy by proving the ribosome a circular translation template for expression of long peptides containing tandem repeats. This revolutionary technique will allow researchers to easily build, study, and experiment with any fiber proteins with sequences either from natural genes or artificial designs. We expect a significantly accelerated development of fibrous protein-based biomaterials with the cmRNA technique.


Assuntos
Proteínas de Artrópodes , Seda , Materiais Biocompatíveis , DNA , RNA Mensageiro/genética , Proteínas Recombinantes/química , Seda/química , Seda/genética , Seda/metabolismo
10.
Int Arch Allergy Immunol ; 183(1): 34-44, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34515115

RESUMO

BACKGROUND: Few data are available concerning the prevalence and risk factors for allergic rhinitis (AR) in school children in Hubei Province which is located in the central part of China. This study investigated the epidemiological features of AR among school children in Hubei Province. METHODS: A cross-sectional questionnaire survey on AR in school children was carried out in 5 cities in Hubei Province by cluster sampling from June to September 2018. Questionnaires were filled out by children and their parents jointly. The diagnostic criteria of AR were according to the SFAR. Questions from the questionnaire were used to examine the pattern of AR. Logistic regression analysis was used to assess the risk factors for childhood allergies. RESULTS: The total prevalence rate of AR was 16.16%, with 24.31% (Wuhan), 4.34% (Xiangyang), 4.31% (Tianmen), 10.92% (Jingmen), and 11.42% (Huangshi), respectively. The prevalence of AR was positively correlated with gross domestic product per capita (p < 0.05). Multivariate analysis revealed that male, city of Wuhan, family history of allergy, food allergy, drug allergy, air purifier, exposure to dust, living in towns or urban area before 2 years old, maternal age for 26-35 years old, and frequent application of antibiotics increased the risk of AR, while daily outdoor time for 1-2 h, daily sleeping time >8 h, siblings, and breastfeeding for >6 months reduced the risk significantly. CONCLUSION: We found the apparent geographic variation of children allergies in Hubei Province. Both genetic and environment factors had impacts on the prevalence of AR in school children. Public policies should specifically target at the local risk factors for different areas.


Assuntos
Rinite Alérgica/epidemiologia , Instituições Acadêmicas , Estudantes , Alérgenos , Criança , Pré-Escolar , China/epidemiologia , Comorbidade , Estudos Transversais , Feminino , Humanos , Masculino , Razão de Chances , Prevalência , Vigilância em Saúde Pública , Rinite Alérgica/etiologia , Fatores de Risco , Estações do Ano , Fatores Socioeconômicos , Inquéritos e Questionários
11.
Pharmacol Res ; 185: 106513, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36252772

RESUMO

cytohesin-2 is a guanine nucleotide exchange factor to activate ARF1 and ARF6, which are involved in various biological processes, including signal transduction, cell differentiation, cell structure organization, and survival. Nevertheless, there is a lack of evidence revealing the role of cytohesin-2 in osteoclast differentiation and in the development of osteoporosis. In this study, we find cytohesin-2 and ARF1 positively regulate osteoclast differentiation and function. Blocking the cytohesin-2 /ARF1 axis with SecinH3 or by genetic silencing of cytohesin-2 inhibits osteoclast formation and function in vitro. In vivo treatment with SecinH3 ameliorates ovariectomy-induced osteoporosis. Mechanistically, RNA-sequencing combined with molecular biological methodologies reveal that the regulatory function of cythohesin-2/ARF1 axis in osteoclast differentiation is mainly dependent on activating the JNK pathway. Further, in addition to the common viewpoint that JNK is activated by IRE1 via its kinase activity, we found that JNK can act upstream and regulate the endoribonuclease activity of IRE1 to promote XBP1 splicing. Both SecinH3 and silencing of cytohesin-2 inhibit JNK activation and IRE1 endoribonuclease activity, leading to the suppression of osteoclast differentiation. Taken together, our findings add new insights into the regulation between JNK and IRE1, and reveal that inhibiting the cytohesin-2/ARF1/JNK/IRE1 axis might represent a potential new strategy for the treatment of post-menopause osteoporosis.


Assuntos
Fatores de Ribosilação do ADP , Osteoporose , Humanos , Fatores de Ribosilação do ADP/fisiologia , Osteoclastos/metabolismo , Fator 6 de Ribosilação do ADP , Osteoporose/tratamento farmacológico , Endorribonucleases/metabolismo , Proteínas Serina-Treonina Quinases
12.
Microb Cell Fact ; 21(1): 235, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369085

RESUMO

BACKGROUND: Natural life systems can be significantly modified at the genomic scale by human intervention, demonstrating the great innovation capacity of genome engineering. Large epi-chromosomal DNA structures were established in Escherichia coli cells, but some of these methods were inconvenient, using heterologous systems, or relied on engineered E. coli strains. RESULTS: The wild-type model bacterium E. coli has a single circular chromosome. In this work, a novel method was developed to split the original chromosome of wild-type E. coli. With this method, novel E. coli strains containing two chromosomes of 0.10 Mb and 4.54 Mb, and 2.28 Mb and 2.36 Mb were created respectively, designated as E. coli0.10/4.54 and E. coli2.28/2.36. The new chromosomal arrangement was proved by PCR amplification of joint regions as well as a combination of Nanopore and Illumina sequencing analysis. While E. coli0.10/4.54 was quite stable, the two chromosomes of E. coli2.28/2.36 population recombined into a new chromosome (Chr.4.64MMut), via recombination. Both engineered strains grew slightly slower than the wild-type, and their cell shapes were obviously elongated. CONCLUSION: Finally, we successfully developed a simple CRISPR-based genome engineering technique for the construction of multi-chromosomal E. coli strains with no heterologous genetic parts. This technique might be applied to other prokaryotes for synthetic biology studies and applications in the future.


Assuntos
Sistemas CRISPR-Cas , Escherichia coli , Humanos , Escherichia coli/genética , Plasmídeos/genética , Cromossomos , Biologia Sintética
13.
Mol Biol Rep ; 49(1): 451-461, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34731371

RESUMO

BACKGROUND: Sulforaphane (SFN) is a kind of isothiocyanate from cruciferous vegetables with extensive anti-tumor activity. Esophageal squamous cell carcinoma (ESCC) is a popular malignancy in East Asia, East and South Africa, while the more efficient medicines and therapeutic strategies are still lack. This study aims to explore the anti-tumor activity of SFN alone and combined with Akt/mTOR pathway inhibitors as well as the potential molecular mechanism in ESCC. METHODS AND RESULTS: Cell proliferation, migration, cell cycle phase, apoptosis and protein expression were detected with MTT assay, clone formation experiment, wound healing assays, flow cytometry and Western blot, respectively, after ESCC cells ECa109 and EC9706 treated with SFN alone or combined with Akt/mTOR inhibitors. Xenograft models were used to evaluate the efficiency and mechanism of SFN combined with PP242 in vivo. The results showed that SFN significantly inhibited the viability and induced apoptosis of ECa109 and EC9706 cells by increasing expression of Cleaved-caspase 9. SFN combined with PP242, but not MK2206 and RAD001, synergetic inhibited proliferation of ESCC cells. Moreover, compared to SFN alone, combination of SFN and PP242 had stronger inhibiting efficiency on clone formation, cell migratory, cell cycle phase and growth of xenografts, as well as the more powerful apoptosis-inducing effects on ESCC. The mechanism was that PP242 abrogated the promoting effects of SFN on p-p70S6K (Thr389) and p-Akt (Ser473) in ESCC. CONCLUSIONS: Our findings demonstrate that PP242 enhances the anti-tumor activity of SFN by blocking SFN-induced activation of Akt/mTOR pathway in ESCC, which provides a rationale for treating ESCC using SFN combined with Akt/mTOR pathway inhibitors.


Assuntos
Indóis/farmacologia , Isotiocianatos/farmacologia , Inibidores de MTOR/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Purinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Sulfóxidos/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Sinergismo Farmacológico , Neoplasias Esofágicas , Humanos , Imunofenotipagem , Camundongos , Modelos Biológicos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Int J Mol Sci ; 23(3)2022 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35163549

RESUMO

Saline-alkaline stress is one of several major abiotic stresses in crop production. Exogenous spermidine (Spd) can effectively increase tomato saline-alkaline stress resistance by relieving membrane lipid peroxidation damage. However, the mechanism through which exogenous Spd pre-treatment triggers the tomato antioxidant system to resist saline-alkaline stress remains unclear. Whether H2O2 and polyamine oxidase (PAO) are involved in Spd-induced tomato saline-alkaline stress tolerance needs to be determined. Here, we investigated the role of PAO and H2O2 in exogenous Spd-induced tolerance of tomato to saline-alkaline stress. Results showed that Spd application increased the expression and activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), glutathione reductase (GR), and the ratio of reduced ascorbate (AsA) and glutathione (GSH) contents under saline-alkaline stress condition. Exogenous Spd treatment triggered endogenous H2O2 levels, SlPAO4 gene expression, as well as PAO activity under normal conditions. Inhibiting endogenous PAO activity by 1,8-diaminooctane (1,8-DO, an inhibitor of polyamine oxidase) significantly reduced H2O2 levels in the later stage. Moreover, inhibiting endogenous PAO or silencing the SlPAO4 gene increased the peroxidation damage of tomato leaves under saline-alkaline stress. These findings indicated that exogenous Spd treatment stimulated SlPAO4 gene expression and increased PAO activity, which mediated the elevation of H2O2 level under normal conditions. Consequently, the downstream antioxidant system was activated to eliminate excessive ROS accumulation and relieve membrane lipid peroxidation damage and growth inhibition under saline-alkaline stress. In conclusion, PAO triggered H2O2-mediated Spd-induced increase in the tolerance of tomato to saline-alkaline stress.


Assuntos
Peróxido de Hidrogênio/metabolismo , Oxirredutases atuantes sobre Doadores de Grupo CH-NH/metabolismo , Solanum lycopersicum/crescimento & desenvolvimento , Espermidina/metabolismo , Diaminas/farmacologia , Solanum lycopersicum/efeitos dos fármacos , Solanum lycopersicum/metabolismo , Estresse Oxidativo , Proteínas de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Salino , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Regulação para Cima , Poliamina Oxidase
15.
J Environ Manage ; 324: 116246, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36162320

RESUMO

Hazardous waste incineration fly ash (HFA) is considered a hazardous waste owing to the high associated concentrations of heavy metals and soluble salts. Hence, cost effective methods are urgently needed to properly dispose HFA. In this study, geopolymers were prepared by alkali-activation technology to stabilize and solidify heavy metals in HFA. In addition, the effects of three different aluminosilicates (metakaolin, fly ash, and glass powder) on the heavy metal immobilization efficiency were investigated. Because the soluble salt content of HFA is too high for their direct placement in flexible landfill sites and water washing can lead to heavy metal leaching, water-washing experiments were conducted after alkali-activation treatment to remove soluble salts. The results suggest that the concentrations of heavy metals leached from geopolymers can satisfy the Chinese Standard limits (GB18598-2019) when the addition of aluminosilicates exceeds 20 wt%. More than 77% of Cl- and >64% of SO42- in geopolymers could be removed via water-washing treatment. The Zn leaching concentration was maintained below approximately 0.52 ppm. After alkali-activation treatment, the water-washing process could efficiently remove soluble salts while inhibiting heavy metal leaching. Sodium-aluminosilicate-hydrate (N-A-S-H) gel, a product of the geopolymerization process in this study, was demonstrated to act as a protective shell that inhibited heavy metal leaching. Hence, HFA-based geopolymers are considered suitable for disposal in flexible landfills.


Assuntos
Metais Pesados , Eliminação de Resíduos , Incineração/métodos , Cinza de Carvão , Resíduos Perigosos , Sais , Metais Pesados/análise , Álcalis , Água , Eliminação de Resíduos/métodos , Resíduos Sólidos/análise , Carbono , Material Particulado
16.
Phytopathology ; 111(7): 1166-1172, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33107780

RESUMO

Fungicide hormesis has implications for the application of fungicides to control plant diseases. We investigated the hormetic effects of the dicarboximide fungicide dimethachlone on mycelial growth and virulence of the necrotrophic plant pathogen Sclerotinia sclerotiorum. Dimethachlone at sublethal doses in potato dextrose agar (PDA) increased the mycelial growth of S. sclerotiorum. After the growth-stimulated mycelia were subcultured on fresh PDA and inoculated on rapeseed leaves, increased mycelial growth and virulence were observed, indicating that hormetic traits were passed down to the next generation. Dimethachlone applied to leaves at 0.002 to 500 µg/ml stimulated virulence, with a maximum stimulation amplitude (MSA) of 31.4% for the isolate HLJ4, which occurred at 2 µg/ml. Dimethachlone-resistant isolates and transformants had a mean virulence MSA of 30.4%, which was significantly higher (P = 0.008) than the MSA for sensitive isolates (16.2%). Negative correlations were detected between MSA and virulence in the absence of any fungicide (r = -0.872, P < 0.001) and between MSA and mycelial growth on PDA (r = -0.794, P = 0.002). Studies on hormetic mechanisms indicated that dimethachlone had no significant effects on expression levels of three virulence-associated genes, that is, a cutinase-encoding gene SsCut, a polygalacturonase gene SsPG1, or an oxaloacetate acetylhydrolase gene SsOah1. The results will contribute to understanding hormesis and have implications for the judicious application of fungicides to control plant diseases.


Assuntos
Ascomicetos , Hormese , Doenças das Plantas , Virulência
17.
Mol Pharm ; 17(5): 1663-1673, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32243177

RESUMO

Glucagon-like peptide-1 (GLP-1) is an incretin (a type of metabolic hormone that stimulates a decrease in blood glucose levels), holding great potential for the treatment of type 2 diabetes mellitus (T2DM). However, its extremely short half-life of 1-2 min hampers any direct clinical application. Here, we describe the application of the heavy chain of human ferritin (HFt) nanocage as a carrier to improve the pharmacological properties of GLP-1. The GLP-HFt was designed by genetic fusion of GLP-1 to the N-terminus of HFt and was expressed in inclusion bodies in E. coli. The refolding process was developed to obtain a soluble GLP-HFt protein. The biophysical properties determined by size-exclusion chromatography (SEC), dynamic light scattering (DLS), circular dichroism (CD), transmission electron microscopy (TEM), and X-ray crystallography verified that the GLP-HFt successfully formed a 24-mer nanocage with GLP-1 displayed on the external surface of HFt. The in vivo pharmacodynamic results demonstrated that the GLP-HFt nanocage retained the bioactivity of natural GLP-1, significantly reduced the blood glucose levels for at least 24 h in a dose-dependent manner, and inhibited food intake for at least 8-10 h. The half-life of the GLP-HFt nanocage was approximately 52 h in mice after subcutaneous injection. The prolonged half-life and sustained control of blood glucose levels indicate that the GLP-HFt nanocage can be further developed for the treatment of T2DM. Meanwhile, the HFt nanocage proves its great potential as a universal carrier that improves the pharmacodynamic and pharmacokinetic properties of a wide range of therapeutic peptides and proteins.


Assuntos
Diabetes Mellitus Tipo 2 , Peptídeo 1 Semelhante ao Glucagon , Animais , Glicemia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Escherichia coli/metabolismo , Ferritinas , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/farmacologia , Insulina/metabolismo , Camundongos
18.
Asian-Australas J Anim Sci ; 33(6): 965-972, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31480151

RESUMO

OBJECTIVE: Astragalus membranaceus root is a well-known traditional Chinese herbal medicine with many biological active constituents. This study was conducted to examine the effects of Astragalus membranaceus root powder (AMP) on growth performance, serum antioxidant and immune response in finishing lambs. METHODS: A total of thirty-six Guangling fat-tailed ram lambs (body weight = 19±2 kg, mean ±standard deviation) were randomly assigned to one of six treatments for a 40 d feeding period, with the first 10 d for adaptation. Treatments consisted of the lambs' basal diets with addition of 0, 5, 10, 15, 20, and 30 g/kg of diet of AMP. RESULTS: Response to supplementation level of AMP was quadratic (p≤0.032) for final weight and ADG with the greatest at 10 g/kg of diet, but dry matter intake was not affected (p≥0.227) by treatments. The increase of AMP supplementation resulted in a quadratic response in contents of triglyceride and creatinine (p<0.05), with the lowest values for 10 and 20 g/kg of diet, respectively. A linear and quadratic decrease was observed in activity of alkaline phosphatase in serum of lambs. As the AMP supplementation increased, the activities of total superoxide dismutase and total antioxidant capacity increased linearly (p≤0.018) and hydroxyl radical (OH-) decreased linearly (p = 0.002). For catalase (CAT) and malondialdehyde (MDA), quadratic (p≤0.001) effects were observed among treatments, with the greatest CAT and lowest MDA values at 10 g/kg AMP. Additionally, supplementing AMP up to a level of 10 or 15 g/kg of diet quadratically increased immunoglobulin and interleukin contents in the serum. CONCLUSION: The results indicated that AMP can be used as natural feed additive in the ration of lambs to improve ADG, antioxidant status, and immune functions, and the optimal dose was 10 g/kg of diet under the condition of this experiment.

19.
Anticancer Drugs ; 30(7): e0747, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31305293

RESUMO

Pyrvinium tosylate (PT) is an anthelminthic drug that has recently been shown to suppress various human cancers. However, whether PT is effective in nasopharyngeal carcinoma (NPC) has not been determined to date. In this work, we show the selective efficacy of PT in NPC while sparing normal nasopharyngeal epithelial cells, and its ability to increase chemosensitivity. We show that PT at 100 and 500 nmol/l significantly inhibits growth and induces apoptosis in several NPC cell lines without affecting normal nasopharyngeal epithelial cells. Using cell culture and xenograft mouse models, PT markedly enhances cisplatin's efficacy in NPC and the combination leads to almost complete tumor inhibition. Mechanism studies show that PT suppresses active, nuclear ß-catenin level and activity and increases Axin level in NPC cells. ß-Catenin overexpression completely reverses the inhibitory effects of PT, confirming that ß-catenin is the molecular mechanism of PT's action in NPC. In addition, the effects of PT on ß-catenin and Axin levels and on Wnt signaling in NPC cells are mediated by its activation of casine kinase 1α. Our work is the first to suggest that Wnt/ß-catenin is a selective target for NPC treatment, and provides the preclinical evidence on the translational potential of PT as a useful addition to the treatment armamentarium for NPC.


Assuntos
Caseína Quinase Ialfa/metabolismo , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Carcinoma Nasofaríngeo/tratamento farmacológico , Compostos de Pirvínio/farmacologia , Proteínas Wnt/antagonistas & inibidores , beta Catenina/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Apoptose , Caseína Quinase Ialfa/genética , Proliferação de Células , Cisplatino/farmacologia , Quimioterapia Combinada , Humanos , Camundongos , Camundongos SCID , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
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